38.1. Introduction to Qmail
Qmail is probably the second most popular UNIX mail server on the Internet, behind Sendmail and in competition with Postfix. Because Sendmail uses a single server process that runs as root, any security hole in that process can allow an attacker to take over an entire system. Qmail was designed to avoid this problem by using multiple server processes and programs, each of which has only the privileges that it needs.
Before you can configure Qmail, you need to understand how Internet email works. Section 37.1 “Introduction to Internet Email” explains pretty much everything you need to know, so read it now if you are unfamiliar with SMTP, MX records, and so on. All the same principals apply to Qmail as well.
The biggest ...
Get Managing Linux® Systems with Webmin™ System Administration and Module Development now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
